1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation. Oracle designates this
7 * particular file as subject to the "Classpath" exception as provided
8 * by Oracle in the LICENSE file that accompanied this code.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
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19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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23 */
24
25 /*
26 * This file is available under and governed by the GNU General Public
27 * License version 2 only, as published by the Free Software Foundation.
28 * However, the following notice accompanied the original version of this
29 * file and, per its terms, should not be removed:
30 *
31 * Copyright (c) 2002 World Wide Web Consortium,
32 * (Massachusetts Institute of Technology, Institut National de
33 * Recherche en Informatique et en Automatique, Keio University). All
34 * Rights Reserved. This program is distributed under the W3C's Software
35 * Intellectual Property License. This program is distributed in the
36 * hope that it will be useful, but WITHOUT ANY WARRANTY; without even
37 * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
38 * PURPOSE.
39 * See W3C License http://www.w3.org/Consortium/Legal/ for more details.
40 */
41
42 package org.w3c.dom.xpath;
43
44
45 import org.w3c.dom.Node;
46 import org.w3c.dom.DOMException;
47
48 /**
49 * The evaluation of XPath expressions is provided by
50 * <code>XPathEvaluator</code>. In a DOM implementation which supports the
51 * XPath 3.0 feature, as described above, the <code>XPathEvaluator</code>
52 * interface will be implemented on the same object which implements the
53 * <code>Document</code> interface permitting it to be obtained by the usual
54 * binding-specific method such as casting or by using the DOM Level 3
55 * getInterface method. In this case the implementation obtained from the
56 * Document supports the XPath DOM module and is compatible with the XPath
57 * 1.0 specification.
58 * <p>Evaluation of expressions with specialized extension functions or
59 * variables may not work in all implementations and is, therefore, not
60 * portable. <code>XPathEvaluator</code> implementations may be available
61 * from other sources that could provide specific support for specialized
62 * extension functions or variables as would be defined by other
63 * specifications.
64 * <p>See also the <a href='https://www.w3.org/TR/DOM-Level-3-XPath/'>Document Object Model (DOM) Level 3 XPath Specification</a>.
65 */
66 public interface XPathEvaluator {
67 /**
68 * Creates a parsed XPath expression with resolved namespaces. This is
69 * useful when an expression will be reused in an application since it
70 * makes it possible to compile the expression string into a more
71 * efficient internal form and preresolve all namespace prefixes which
72 * occur within the expression.
73 * @param expression The XPath expression string to be parsed.
74 * @param resolver The <code>resolver</code> permits translation of
75 * prefixes within the XPath expression into appropriate namespace URIs
76 * . If this is specified as <code>null</code>, any namespace prefix
77 * within the expression will result in <code>DOMException</code>
78 * being thrown with the code <code>NAMESPACE_ERR</code>.
79 * @return The compiled form of the XPath expression.
80 * @exception XPathException
81 * INVALID_EXPRESSION_ERR: Raised if the expression is not legal
82 * according to the rules of the <code>XPathEvaluator</code>i
83 * @exception DOMException
84 * NAMESPACE_ERR: Raised if the expression contains namespace prefixes
85 * which cannot be resolved by the specified
86 * <code>XPathNSResolver</code>.
87 */
88 public XPathExpression createExpression(String expression,
89 XPathNSResolver resolver)
90 throws XPathException, DOMException;
91
92 /**
93 * Adapts any DOM node to resolve namespaces so that an XPath expression
94 * can be easily evaluated relative to the context of the node where it
95 * appeared within the document. This adapter works like the DOM Level 3
96 * method <code>lookupNamespaceURI</code> on nodes in resolving the
97 * namespaceURI from a given prefix using the current information
98 * available in the node's hierarchy at the time lookupNamespaceURI is
99 * called. also correctly resolving the implicit xml prefix.
100 * @param nodeResolver The node to be used as a context for namespace
101 * resolution.
102 * @return <code>XPathNSResolver</code> which resolves namespaces with
103 * respect to the definitions in scope for a specified node.
104 */
105 public XPathNSResolver createNSResolver(Node nodeResolver);
106
107 /**
108 * Evaluates an XPath expression string and returns a result of the
109 * specified type if possible.
110 * @param expression The XPath expression string to be parsed and
111 * evaluated.
112 * @param contextNode The <code>context</code> is context node for the
113 * evaluation of this XPath expression. If the XPathEvaluator was
114 * obtained by casting the <code>Document</code> then this must be
115 * owned by the same document and must be a <code>Document</code>,
116 * <code>Element</code>, <code>Attribute</code>, <code>Text</code>,
117 * <code>CDATASection</code>, <code>Comment</code>,
118 * <code>ProcessingInstruction</code>, or <code>XPathNamespace</code>
119 * node. If the context node is a <code>Text</code> or a
120 * <code>CDATASection</code>, then the context is interpreted as the
121 * whole logical text node as seen by XPath, unless the node is empty
122 * in which case it may not serve as the XPath context.
123 * @param resolver The <code>resolver</code> permits translation of
124 * prefixes within the XPath expression into appropriate namespace URIs
125 * . If this is specified as <code>null</code>, any namespace prefix
126 * within the expression will result in <code>DOMException</code>
127 * being thrown with the code <code>NAMESPACE_ERR</code>.
128 * @param type If a specific <code>type</code> is specified, then the
129 * result will be returned as the corresponding type.For XPath 1.0
130 * results, this must be one of the codes of the
131 * <code>XPathResult</code> interface.
132 * @param result The <code>result</code> specifies a specific result
133 * object which may be reused and returned by this method. If this is
134 * specified as <code>null</code>or the implementation does not reuse
135 * the specified result, a new result object will be constructed and
136 * returned.For XPath 1.0 results, this object will be of type
137 * <code>XPathResult</code>.
138 * @return The result of the evaluation of the XPath expression.For XPath
139 * 1.0 results, this object will be of type <code>XPathResult</code>.
140 * @exception XPathException
141 * INVALID_EXPRESSION_ERR: Raised if the expression is not legal
142 * according to the rules of the <code>XPathEvaluator</code>i
143 * <br>TYPE_ERR: Raised if the result cannot be converted to return the
144 * specified type.
145 * @exception DOMException
146 * NAMESPACE_ERR: Raised if the expression contains namespace prefixes
147 * which cannot be resolved by the specified
148 * <code>XPathNSResolver</code>.
149 * <br>WRONG_DOCUMENT_ERR: The Node is from a document that is not
150 * supported by this <code>XPathEvaluator</code>.
151 * <br>NOT_SUPPORTED_ERR: The Node is not a type permitted as an XPath
152 * context node or the request type is not permitted by this
153 * <code>XPathEvaluator</code>.
154 */
155 public Object evaluate(String expression,
156 Node contextNode,
157 XPathNSResolver resolver,
158 short type,
159 Object result)
160 throws XPathException, DOMException;
161
162 }